Both answers are not adequate to use regular notes of SA 230 to find out all points of advantages and utilityyou can use below content from our SA 230 notesNeed Purpose of Audit Documentation(Basic Purpose)Audit documentation that meets the requirements of this SA and the specific documentation requirements of other relevant SAs provides:Evidence of the auditor’s basis for a conclusion about the achievement of the overall objectives of the auditor; andEvidence that the audit was planned and performed in accordance with SAs and applicable legal and regulatory requirements.(Additional Purpose)Audit documentation serves a number of additional purposes, including the following:Assisting the engagement team to plan and perform the audit. Enabling the engagement team to be accountable for its work.Assisting members of the engagement team responsible for supervision to direct and supervise the audit work, and to discharge their review responsibilities in accordance with SA 220.Enabling the conduct of quality control reviews and inspections in accordance with SQC 1.Retaining a record of matters of continuing significance to future audits. It acts as an evidence in the court of law when a charge of negligence is brought against the auditor.It acts as the process of planning for the auditor so that he can estimate the time that may be required for checking the schedules.Enabling the conduct of external inspections in accordance with applicable legal, regulatory or other requirements. (Like Peer Review &amp; Review by Quality Review Board).